Fire-escape.



G. H. JOHNSON.

FIRE ESCAPE.

APPLIOATION FILED APR. 1, 1910.

Patented Sept 27, 1910..

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G. H. JOHNSON.

'FIRE ESCAPE. APPLICATION nnnn APR. 1, 1910.

Patented Sept. 27, 1910.

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FIRE-ESCAPE.

Specification of Letters Patent.

Patented Sept. 27, 1910.

Application filed April 1, 1910. Serial m'sseneo.

To all whom it may concern:

Be it known that I, GEORGE H. JOHNSON, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a new and useful Improvement in F ire-Escapes, of which thefollowing is a specification.

My invention relates to certain new and useful improvements in fireescapes and is fully described and explained in the specification andshown in the accompanying drawing, in which:

Figure 1 is a side elevation of my improved device; Fig. 2 is a top planof the counterweight channel-iron on a somewhat larger scale than thatused in Fig. 1; Fig. 3 is a perspective view of one end of the same on astill larger scale; Fig. 4 is a section in the line 4 of Fig. 1; Fig. 5isa top plan of one of the stairs; Fig. 6 is an elevation of one of thestairs; Fig. 7 is a sectional perspective View showing the counterweightchannel, a spacer and the adjacent side-bars of the stair; Fig. 8 is aperspective view of one of the braces; Fig. 9 is a section on the line 9of Fig 5, and Fig. 10 is a broken perspective view of the counterweightand the end of the channel-iron on which the same is mounted.

Referring to the drawings, A. are two longitudinally-extending flat barswhich are located in pairs in the same plane, similar pairs of barsbeing disposed on opposite sidesof the stairway as shown in Fig. 4:.These flat-bars make up the longitudinal members of the stairway. Thetreads of the stairs extend transversely between said bars A in properangular relation with. respect thereto, t e tread-construction beingbest illustrated in Figs. 5, 6 and 9. It will be seen in these figuresthat the bars A carry tread-ends B, which are connected by crossbarsb,'which aresquare in cross-section with their angles upward, accordingto the requirements of modern practice. 'lhese crossbars make up thebody of the tread. Below these bars in the 'front and rear of the treadsrespectively are truss-rods B struts.

6 being interposed between said truss-rods and the cross-rods Z),and thetruss-rods being capable of being tensioned by means of nuts at theirends whereby to support, in a proper manner, the central portion of thetreads illustrated in Fig. 6. The construction formed by the side-barsand treads set together in the manner illustrated, provides a lower fireescape section of desirable form, the same being pivoted upon ahorizontal pivot C, so as to be swung up and down in the usual way. Thestair-section thus formed is counterweigl'ited upon one side only in thefollowing, manner.

1) is an inwardly facing channel iron, which extends alongside the upperportion of the stair-section and beyond the pivot of the same, the samebeing supplied with a weight D at its free-end, the said weight servingto counterweight the free-end of the stair. Before said counterweightchannelbar D is secured to the stair-section proper, the lower endthereof is twisted in the manner illustrated in Figs. 2 and 3, that is,the edge thereof, which will be uppermost in the completed structure istwisted outward, that is in the direction away from theuncounterweighted side of the stairway. It is then firmly bolted orotherwise secured to the stair-section by any desired mechanism and theinitial twist of the channel-bar will serve to keep the stairway in itsproper fiat relation, regardless of any tendency which theuncounterweighted side of the stair may have to sag down. In the form ofconstruction herein illustrated, spacers E are interposed bctween thechannel-bar and stairsection, the same consisting of flat-plates of suchsize as to fit transversely Within the channel-bars and notched toreceive the sidebars of the stair-section. Theispacers have yokesstamped from their planes in opposite directions to receive and guidethe bolts which secure the channel-bar to the stair.- section.

For the purpose of rendering the stairsection transversely rigid to asgreatan extent as is possible the braces F are secured therein, the saidbraces consisting of angleirons f bent upward at the ends and raised bycorner-plates f in'the form of right triangles. The braces F maybebolted into the stair-section in any desired position, but for greaterconvenience they are in practice secured by the same nuts which securethe counterweight channel-bars in position; the manner of assemblingbeing clearly illustrated in Fig. 4.

I realize that considerable variation is possible in the details ofconstruction of my improved device, without departing from the spirit ofmy invention, and I do not intend, therefore, to limit myself to thespecific form herein shown and described.

What I claim as new and desire to secure by Letters Patent is:

l. A fire escape, comprising a pivoted stair-section, a counterweightthereon, and a twisted member secured to the counterweighted side ofsaid stair-section, the twist being in a direction to tend to elevatethe opposite side of the stair.

2. In combination a pivoted stair-section, a twisted member secured toone side thereof, the twist being in a direction to tend to elevate theopposite side of the stair, said member extending beyond the pivot ofthe stair and carrying a counterweight at its end.

3. In combination a pivoted stair-section, a member secured to one sideof the stair and extending beyond the pivot thereof, a' counterweightcarried by the free-end of said member, said member being twisted priorto this application to the stair for the purpose set forth.

&. In combination a pivoted stair-section, a channel-bar bolted to theside of the stairsection, and having its upper edge initiallytwistedaway from the stair-section and a counterweight secured to the end ofthe channel-bar which extends beyond the pivot of the stair-section.

5. In combination, side plates and treads forming a-pivotedstair-section, an initially twisted member-secured to one side of thestair-section and having a counterweight be yond the pivot of thestair-section, and braces connecting the said bars of the stairsectionfor rendering the stair-section transversely rigid.

6. In combination a pivoted stair-section having side plates, a iinitially twisted channel-bar at one side of the stair-section andextending beyond the pivot thereof, a 'coun terweight applied. to thefree-end of said stair-section and spacers in the fornrot' fiat platesfitting within the channel-bar notched to receive the adjacent sideplates and having bolt-guiding yokes stamped from its body.

In testimony whereof, I have hereunto set my hand at Chicago, Illinois,in the presence of two subscribing witnesses.

GEORGE E. JOHNSON. Inpresence of J. G. AnoniisoN, R. A. SOHAEFER.

